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161.
Evolution from a solitary way of life to sociality involves changes in the modalities of within-population aggression. This
paper is concerned with environmental causes of variation in aggression within the complex of mole-rat species Spalax ehrenbergi. We focus on physiological constraints associated with aggressive behaviour, i.e. those resulting from emotional arousal
and thus stress. Aggression, social stress sensitivity and urine osmolarity were studied in males of two chromosomal species
of Spalax ehrenbergi, 2n = 52 (occurring in cool humid areas) and 2n = 60 (occurring in warm arid zones). Males with 2n = 52 reached a higher level of within-population aggression during a 3-round tournament (an average, 488 ± 140 acts) than
males with 2n = 60 (163 ± 54 acts). The species with 2n = 52 displayed a higher corticosterone response after a social encounter (in average, 5.15 ± 0.54 μg/100 ml) than that with
2n = 60 (3.0 ± 0.3 μg/100 ml) whereas resting levels of this hormone were low and not different between the two species. Urine
osmolarity was significantly higher in males with 2n = 60 (331.9 ± 18.6 mmol/kg) than males with 2n = 52 (267.3 ± 10.9 mmol/kg). Considering the overall general trend urine osmolarity tended to be negatively related to the
level of aggression, while corticosterone levels tended to vary positively with aggressiveness (Fig. 3). Our results allow
further discussion of the hypothesis that high levels of aggression could be selected against in arid habitats due to their
physiological correlates (decrease in water economy, increased corticosterone leading to potential energy mobilisation and
loss). We propose that behavioural ecophysiology could have contributed to the radiation of the S. ehrenbergi superspecies into increasingly arid environments, and may favour evolution toward social tolerance.
Received: 10 June 1995/Accepted after revision: 25 October 1995 相似文献
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根据武钢自身安全管理工作的需要,提出了一套以科学的方法、务实的态度、严谨的作风,开展以危险辨识、风险评价、危险控制为核心的职业安全健康管理工作思路,从而使生产环境、职工素质、管理水平等方面均取得较大改善和提高,效果显著。 相似文献
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Our study examines how personality and coping influence soldiers' psychological health among 648 US Army personnel who were at that time deployed in Iraq at the height of an insurgency. Conscientiousness, neuroticism, and extraversion were associated with different coping behaviors, and these were in turn related to psychological distress. Conscientiousness was positively associated with problem‐focused coping and negatively with avoidance coping, whereas neuroticism was most positively associated with avoidance coping. Extraversion was positively related to both seeking social support and avoidance coping. As expected, avoidance coping was positively associated with psychological distress. Coping style explained more variance in the relationship between personality and distress among soldiers who perceived higher levels of threat, thus supporting a moderated mediation hypothesis. We discuss implications for facilitating the stress coping of workers who face acute and potentially traumatic stress exposures. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
170.
In order to obtain the characteristics of in situ stress field in outburst mining area, using the hollow inclusion (HI) technique to measure the in situ stress of coal and gas outburst mining area. The measurement sites located in northeast, middle and east of china, which include eight mining areas such as Fuxin, Pingdingshan, Hebi and Huainan. Base on the analysis of measurement data from outburst mining area, conclusions could be obtained as follow: (a) major principal stress and minor principal stress is horizontal stress and interim principal stress is vertical stress, and the type of outburst area’s stress field is dynamic stress field; (b) the major principal stress and minor principal stress are higher than other regions and the tectonic stress is outstanding; and (c) the ratio of major principal and vertical stress is decrease with the increase of depth and the type of stress field is likely transfer dynamic to static. Thus, in situ stress plays a key role during the occurring and development of coal and gas outburst, which is an important reason of severe outburst in China. 相似文献